JPS5916970A - Method for detecting and controlling evaporation amount of evaporation material in ion plating - Google Patents

Abstract

PURPOSE:To detect the available evaporation amount of an evaporation material from an evaporation source simply and accurately, by measuring the current value or the voltage value of a probe of ion plating when voltage applied to said probe or a current flowed therethrough is made constant. CONSTITUTION:In ion plating wherein the evaporation material 5 in an evaporation source 2 is evaporated under heating by an evaporation power source 6 in a bell jar 1 while a constant current Ip is flowed through a probe 3 by a constant- current power source 10 to form a plasma state and the evaporated substance is adhered on a substrate 4 to which negative voltage is applied by a DC power source 8 to form a thin film, probe voltage Vp between the probe 3 and earth is measured by a DC voltmeter 11. Because the probe voltage Vp almost accurately corresponds to the film thickness on the substrate 4, an available evaporation amount can be detected by said measured value. In addition, a current flowed through the evaporation source 2 is changed so as to keep the probe voltage Vp constant and the available evaporation amount of the evaporation material 5 can be controlled so as to be kept constant.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting the effective amount of evaporation of an evaporator in ion blating, and a method for controlling the amount of evaporation based on the detection result.

Ion blating is attracting attention as a method to strengthen the adhesion strength of vapor deposition and increase wraparound.
□, and various methods have been put into practical use.

As shown in FIG. 1, neon blating, which is the object of the present invention, consists of an evaporation source 2 such as an electron beam evaporation source, a globe 6, and a substrate (in this specification, a thin film is entirely The members to be formed are placed at a complete distance from the evaporation source 2 with a power source 6 for heating and evaporating the evaporation material 5, and the probe 6 is heated and evaporated by a power source 7 for evaporation. A full positive voltage is applied to attract the electrons emitted from the evaporation source 2 and the evaporation material 5 and cause them to collide with the evaporation material gas or atmospheric gas to generate a plasma state, and a compound is formed by the reaction between the evaporation material or the evaporation material and the atmospheric gas. In this method, a thin film is formed by adhering the material to the substrate 4.

In the example shown in Figure 1, the evaporation source 2 is an electron beam using an E-type electron gun that emits an electron beam using a heater and a negative high-voltage electrode, deflects it with a magnet, and irradiates the evaporated material on a water-cooled crucible. Although all evaporation sources are used, the present invention is not limited to this, and evaporation source sounds using resistance heating or high-frequency heating may also be used.

Further, a negative voltage (100 to 2
00V)k is applied, but the substrate 4 may be kept in an insulated state or a grounded state.

When performing ion blating in this manner, even if the power supplied to the evaporation source 2 is constant, the effectiveness of the evaporator 5 may vary due to changes in the pressure inside the bell jar 1, changes in atmospheric gas concentration, and other various conditions. The amount of evaporation changes.

In this specification, the term "effective evaporation amount" refers to the amount effective for forming a thin film out of the total evaporation amount of the evaporator.

Therefore, in order to fully form a thin film with the desired thickness and structure, it is necessary to accurately detect the total amount of effective evaporation of the evaporator during ion blating, and furthermore, it is necessary to control the evaporation amount to keep it constant. It becomes necessary to do so.

Therefore, in the past, a crystal film thickness meter was generally used, and the crystal resonator was inserted into a bell jar, and the film thickness was measured by changing the oscillation frequency depending on the amount of evaporated material attached, and the rate of change was The total effective evaporation amount of evaporation material was estimated by

However, in this method of detecting the amount of evaporation, since the entire amount of effective evaporation is detected in a contact manner, it is not possible to accurately know the entire amount of evaporation, and depending on the evaporation material used, measurement may not be possible.

For example, when titanium is used as an evaporator to form a thin film of TiN, which is a compound with titanium or nitrogen,
When this Ti or TiN film is applied to a crystal resonator, the strain is large, causing oscillation failure, and the film adhering to the grass peels off, making it impossible to measure the film thickness. It was not possible to accurately determine the effective amount of titanium evaporated.

Therefore, it is difficult to control the film so that the desired film thickness is always obtained.

This invention was made in response to these problems in conventional ion blating, and is used as a total evaporation material for substances such as titanium, which are difficult to measure with a quartz film thickness meter. The purpose of the present invention is to simply and accurately detect the effective evaporation amount continuously during ion blating, and to keep the effective evaporation amount constant based on the detection results.

Therefore, in the first invention, in the above-mentioned ion blating, the voltage applied to the probe VC or the current flowing when the voltage is kept constant and the voltage flowing when the voltage is kept constant.
The present invention provides a method for detecting the effective amount of evaporation material from an evaporation source based on the current value or the voltage value of the globe when the current is held constant.

Further, the second invention is such that the electric power supplied to the evaporation source is changed by applying Lir to the current value flowing through the globe or the voltage value of the globe to maintain the total estimated effective evaporation amount of the evaporation material. The method for controlling the evaporation amount of the evaporation material (1h1) is provided.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to FIGS.

FIG. 2 is a block diagram of the ion brating device to be implemented in the first inspection.The difference from the device in FIG.
During ion grating, glove 6
The voltage (hereinafter referred to as 1-globe force pressure) generated between Vp and earth (the crucibles of bell jar 1 and evaporation source 2 are grounded) can be measured with a DC ammeter 11.

In such an ion blating device, titanium Tik is used as the evaporator 5, and nitrogen N2 is placed inside the bell jar 1.
Taking as an example the case where a thin film of titanium oxide TiN is formed on the surface of the substrate 4 while injecting the The results are shown in FIG. 3 based on all experimental results.

This figure 6 shows the amount of nitrogen injected, the pressure inside the bell jar, the cooling state of the crucible of evaporation source 2, and the evaporation of titanium Ti while maintaining the flow value 11)'k120A through the globe B by a constant current source 1U. The relationship between E/B power and globe voltage when ion blating is performed while changing various conditions such as area is shown. The lower the curve, the thicker the film formed within the same time.

It was also found that approximately the same film thickness could be obtained in any row of cows if the globe voltage was the same. Furthermore, the lower the probe voltage is, the thicker the film becomes, and no matter how other conditions are changed, this probe voltage almost exactly corresponds to the film thickness, that is, the effective evaporation amount of the evaporation material 5.

Therefore, by measuring the value k of this globe' solder pressure p, the entire effective amount of evaporation of the evaporation material 5 can be detected.

In FIG. 4, the globe voltage Vp is kept constant by using a constant voltage power source instead of the constant current power source 1° in the device shown in FIG.
) E / when measured using a flow meter sound for Ip total'
B is a diagram showing the relationship between the four forces and the probe current.

This example also uses titanium as the evaporator and nitrogen N2
The parameters were set by changing various conditions other than the probe voltage when forming a thin TiN film by implanting TiN. Moreover, this probe current corresponds almost exactly to the effective evaporation amount of the evaporation material.

Therefore, if all values of this globe current Ip are measured,
Thereby, the effective amount of evaporation of the evaporation material can be detected.

Next, FIG. 5 is a block configuration diagram of an ion blating apparatus implementing the second invention.

In this embodiment, like the embodiment shown in FIG. 2, a constant current is applied to the probe 6 by a constant current source 10.

The lobe voltage Vp is detected by the voltage detection circuit 12.

On the other hand, the globe voltage value Vs'ff:ff: constant pressure setting circuit 16 necessary to obtain the desired effective evaporation amount of the evaporation material 5
This set value Vs is set in advance during ion blating by an error detection circuit 14 using a differential amplifier or the like.
A signal Se corresponding to the difference between the probe and the actual probe is output.

This signal Se is input to the i control terminal of the evaporation power source 16 as a proportional, integrated, or differentiated signal SC according to the thickness of the 4g Se through a PID circuit, and the electric power ( E/B' (force) is varied so that the globe voltage Vp and force i become constant.

For example, when the globe voltage Vp rises above the set value Vs, if the evaporation power source 16 is controlled so that the E/B' torque becomes electric power as shown in FIG. , the set value Vs.

In this way, the globe' turtle pressure Vp k constant value V
By controlling T to be equal to s, even if other conditions change, for example, the effective evaporation amount of Ti can be kept constant.
A thin film of iN can be formed over the entire substrate 4.

Furthermore, a constant pressure source is used in place of the constant current power source 10 in FIG. The evaporation power source 16 is controlled according to the difference to generate a globe current Ip.
'ff: Even if it is made to match the set value, the entire thin film can be formed while keeping the evaporation amount of the evaporator constant.

By the way, when forming a thin TiN film on the exterior of a watch or on the surface of an ornament, for example, the color changes depending on the ratio of 'ri, so conventionally it was always difficult to achieve the desired color, but this invention has now been implemented. Then, the total effective evaporation amount of Ti can be controlled to a desired value, and the color of the TiN thin film can also be easily controlled. Furthermore, control of film thickness becomes easier.

This invention is not limited to the formation of thin films of TiN (T
1+ TtC+ 6 or silicon S as evaporator
i, ') It can be similarly applied to ion blasting in which other substances such as ruconium Zr and hafnium Hf are used to form a thin film entirely of the evaporated substance itself or a compound of it and an atmospheric gas.

As explained above, according to the first invention, it is possible to easily and accurately perform ion blating, which uses all evaporation materials, such as titanium, for which the amount of evaporation cannot be measured with a quartz film thickness meter. The effective evaporation amount can be continuously detected during all ion blating, so the composition, color, and
You can know everything about the film thickness, etc., making it easier to control it.

Furthermore, according to the second invention, since the effective evaporation amount of the evaporator during ion blating can be kept constant regardless of changes in other conditions, a predetermined total film thickness can be obtained depending on the duration. It is also easy to keep the composition and color of the film constant.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of an ion brating apparatus to which the present invention is applied. FIG. 2 is a configuration diagram showing an example of an ion brating device implementing the first invention. Figures 6 and 4 show T
Shows the relationship between the E/B% force and the probe voltage when the globe current is kept constant, and the relationship between the E/B'K force and the probe current when the globe voltage is kept constant when forming the entire iN thin film. Fig. 5 is a block configuration diagram showing an example of an ion brating device that fully implements the second invention. 1... Bell jar (vacuum container) 2... Evaporation source 6...
・Probe 4...Substrate 5...Evaporation material
10...Constant current power supply 11...DC voltmeter
12... Voltage detection circuit 16... Evaporation power supply E/B cage (KW) Fig. 5

Claims (1)

[Scope of Claims] 1. An evaporation source, a globe, and a substrate are arranged with a full distance between them in a vacuum container, the evaporation material is completely evaporated by the evaporation source, and a plasma state is generated by the globe,
In ion blating, in which an evaporated substance or a compound resulting from a reaction between the evaporated substance and atmospheric debris is deposited on the substrate to form a thin film, the voltage applied to the globe or the current k applied to the globe is kept constant, and the voltage is kept constant. A method for detecting the amount of evaporation of evaporation material, characterized in that the effective amount of evaporation of evaporation material from the evaporation source is detected based on the value of the current flowing at a certain time or the voltage value of the globe when the current is completely constant. 2. Arranging an evaporation source, a globe, and a substrate at intervals in a vacuum container, evaporating an evaporation material by the evaporation source, and generating a plasma state by the probe,
In ion blating in which a thin film is formed by depositing all of the evaporated substances or compounds resulting from the reaction between the evaporated substances and the atmospheric gas onto the substrate, when the voltage applied to the globe or the current k applied to the globe is kept constant, when the voltage is kept constant. The electric power supplied to the evaporation source is changed according to the flowing current value or the voltage value of the globe when the current is constant, so that the total effective evaporation amount of the evaporation material is kept constant. Method for controlling the amount of evaporation material.